Neighbor information (NBR-INF), which is usually transmitted through some control messages such as neighbor advertisement message in IEEE 802.16 standard, allows mobile stations in wireless communication system to know the information of neighboring cells or networks. Thereby, mobile stations can facilitate their neighbor cell scanning, neighbor cell monitoring, cell selection, network selection, handover and so forth according to the information of neighboring cells or networks.
NBR-INF provides details of neighbor cell information to facilitate handover, network selection and network reentry operations. For example, IEEE 802.16 system defines the neighbor advertisement management message, MOB_NBR-ADV, to describe characteristics of neighboring base stations to potential mobile station(s) seeking initial network entry or handover. The characteristics may contain physical layer (PHY) information, handover information, service-supporting information, downlink or uplink channel information of each of neighboring of base stations. NBR-INF is usually broadcasted periodically in a macro-cell deployment. The advantages of periodic broadcast are: the NBR-INF is delivered for possible large amount of mobile stations in a simple procedure on base stations; the NBR-INF is expectable for non-specific mobile stations. However, if there is only a small amount of mobile stations in the cell (e.g., in a femto cell environment or a Home eNodeB environment), and the neighbor topology or the neighbor configurations change seldom, the overhead of NBR-INF will be generated periodically. Moreover, the overhead would be considerable if the size of a NBR-INF is very large due to a lot of neighbor cells. Therefore, it is an important concern to reduce overhead of the NBR-INF and make delivery of the NBR-INF flexible.